Types of angles (right, acute, obtuse, flat) - Examples, Exercises and Solutions

Definition of Obtuse Angle

An obtuse angle is an angle that measures more than90° 90° degrees, but less than 180° 180° degrees.

Acute angles can appear in triangles, parallelograms, and other geometric shapes.

Obtuse Angle

A1 - Obtuse Angle

Practice Types of angles (right, acute, obtuse, flat)

Exercise #1

True or false?

One of the angles in a rectangle may be an acute angle.

Video Solution

Step-by-Step Solution

One of the properties of a rectangle is that all its angles are right angles.

Therefore, it is not possible for an angle to be acute, that is, less than 90 degrees.

Answer

False

Exercise #2

True or false?

The sum of two acute angles can be greater than 180 degrees?

Video Solution

Answer

False.

Exercise #3

Does the drawing show an adjacent angle?

Video Solution

Answer

Not true

Exercise #4

Does the drawing show an adjacent angle?

Video Solution

Answer

Not true

Exercise #5

Choose the appropriate triangle according to the following:

Angle B equals 90 degrees.

Video Solution

Answer

AAABBBCCC

Exercise #1

Which of the angles is not an obtuse angle?

Video Solution

Answer

Exercise #2

Which of the following angles is a plane angle?

Video Solution

Answer

Exercise #3

Which of the following angles is obtuse?

Video Solution

Answer

91°

Exercise #4

Which of the following angles is obtuse?

Video Solution

Answer

Exercise #5

Which figure shows a right angle?

Video Solution

Answer

Exercise #1

Which figure depicts a right angle?

Video Solution

Answer

Exercise #2

Which of the following angles are obtuse?

Video Solution

Answer

None of the options

Exercise #3

If the two adjacent angles are not equal to each other, then one of them is obtuse and the other acute.

Video Solution

Answer

True

Exercise #4

Does the drawing show an adjacent angle?

Video Solution

Answer

True

Exercise #5

Does the drawing show an adjacent angle?

Video Solution

Answer

Not true

Topics learned in later sections

  1. Right angle
  2. Acute Angles
  3. Plane angle
  4. Angle Notation
  5. Angle Bisector
  6. The Sum of the Interior Angles of a Triangle
  7. Sides, Vertices, and Angles
  8. Types of Angles
  9. Sum and Difference of Angles
  10. Sum of Angles in a Polygon
  11. Exterior angles of a triangle